How dental teams can help patients with temporomandibular disorders receive general dental care: An International Delphi process.

BACKGROUND: Many patients with temporomandibular disorders (TMD) find it difficult to undergo dental care due to challenges caused by their condition, previous temporomandibular joint surgery or invasive dental procedures, and the impact of comorbid conditions. Managing routine dental care for some patients with TMD can be seen as challenging by some dental practitioners. OBJECTIVE: The objective of this study was to work with patients experiencing TMD and clinicians to co-produce recommendations aimed at helping general dentists to provide routine dental care for patients with TMD. METHODS: A modified Delphi process was used to co-produce recommendations. Six patients experiencing TMD, patient advocates and seven clinicians took part, including international TMD clinicians. Two meetings were held with patient participants, mediated by a trained facilitator. Recommendations suggested by patient participants were distributed to clinicians who were asked to add additional suggestions, but not to modify patients' recommendations unless to aid clarity. Additional themes were identified from the existing literature, and the recommendations were then reviewed by the International Network for Orofacial Pain and Related Disorders Methodology (INfORM) consortium. RESULTS: Recommendations were given to support patients before, during and after dental treatment. Participants identified specific and practical recommendations to help patients with TMD receive routine dental care, but also emphasised the need for professionals to listen sensitively to patients' concerns and work with patients in an empathetic and non-judgmental way. CONCLUSION: These recommendations, co-developed with patients experiencing TMD, should help dental professionals to provide supportive general dental care for patients with TMD.

Does professional experience save teeth? A survey among prosthodontists.

OBJECTIVES: The aim of this study is to investigate the effect of clinical experience and educational background on clinical decision-making of dentists presented with two prosthodontic cases. METHODS: A questionnaire-based survey was performed among 66 prosthodontists who were divided into two groups. The first group included clinicians from Belgium, Germany, and the Netherlands covering a wide spectrum of dental experience. The second (specialized) group consisted of German dentists performing their last module of a 3-year postgraduate master program in prosthodontics. Two patient scenarios of different complexities were presented to the participants who were asked to make an educated choice among seven therapeutic options. RESULTS: Sixty-six dentists participated. For case #1, 22 therapeutic suggestions were offered within the international group (variation 54%), while 17 options were chosen in the specialized group (variation 68%). For case #2, five (variation 12%) and four (variation 16%) different therapeutic options were planned in the groups, respectively. Treatment planning in combination with implants was clearly preferred by dentists with an experience of 20 years or less. Conversely, participants with more experience favored more conventional treatments. All differences were statistically significant (p < 0.05). CONCLUSION: Clinicians' experience and educational background had a clinically relevant influence on decision-making and treatment planning. A clear preference for implant-free therapies was noted for dentists with more than two decades of professional experience. CLINICAL SIGNIFICANCE: In complex cases, clinicians with more than 20 years of professional experience tend to save questionable teeth rather than to resort to implants. This interindividual variation might less likely occur when more external evidence is taken into account during the decision-making process.

Labrets in Africa and Amazonia: medical implications and cultural determinants.

The custom of wearing labrets has a long tradition. Labrets appeared independently several thousand years ago in various culture groups in Asia, Europe, Africa and the Americas. Today, apart from diverse body modifications as increasingly practiced in western civilisations, lip plates and plugs are found among a small number of tribal groups only in Africa and Amazonia. We summarise the history of labrets in different societies, describe medical consequences of wearing lip plates and plugs for jaws and teeth and address relevant cultural issues.

Infant oral mutilation in East Africa - therapeutic and ritual grounds.

This paper reviews the practice and ritual traditions of infant oral mutilation, drawing on a literature search in PubMed and Google Scholar, historical reports, relevant textbooks, NGO materials and personal observations of the authors.

Prevalence of self-reported jaw pain in Germany: two cross-sectional surveys of the general German population.

OBJECTIVES: This study evaluated the prevalence of jaw pain as a local, regional, or widespread pain condition and its association with psychosocial variables in a large representative group of the general population from all regions in Germany. METHODS: In two representative samples consisting of 2524 and 2515 subjects, respectively, the 7-day and 3-month pain prevalences were measured by using the Regional Pain Scale (RPS). Somatic symptom burden (somatization) and pain-related depression were assessed with the Patient Health Questionnaire and the Somatic Symptom Scale, respectively. Binary logistic regression was chosen to calculate the associations between demographic and psychological clinical predictor variables with jaw pain. RESULTS: The 7-day jaw pain prevalence was 4.0 % (95 % CI = 3.2-4.8). Of the subjects with jaw pain, only 9 % had local pain (1 pain site), while the remaining 91 % reported regional pain (2-5 pain sites), or widespread pain (6-19 pain sites). The 3-month prevalence of generally present jaw pain was 0.9 % (95 % CI = 0.6-1.0). Regional or widespread pain was present in 82 % of the participants. Jaw pain was predicted by somatic symptom burden (past 7 days, OR = 1.15 [95 % CI = 1.09-1.22]; past 3 months, OR = 1.13 [95 % CI = 1.02-1.25]), but not by depression. CONCLUSIONS: Most individuals with jaw pain have additional pain in other anatomical regions. They might also exhibit a greater risk for pain-associated somatic symptom burden. CLINICAL RELEVANCE: Assessment of pain distribution in the whole body and the use of a psychometric screening questionnaire for somatic symptom burden are recommended for individuals presenting with jaw pain in a clinical setting.

Disk displacement, eccentric condylar position, osteoarthrosis - misnomers for variations of normality? Results and interpretations from an MRI study in two age cohorts.

BACKGROUND: Clinical decision-making and prognostic statements in individuals with manifest or suspected temporomandibular disorders (TMDs) may involve assessment of (a) the position of articular disc relative to the mandibular condyle, (b) the location of the condyle relative to the temporal joint surfaces, and (c) the depth of the glenoid fossa of the temporomandibular joints (TMJs). The aim of this study was twofold: (1) Determination of the prevalence of these variables in two representative population-based birth cohorts. (2) Reinterpretation of the clinical significance of the findings. METHODS: From existing magnetic resonance imaging (MRI) scans of the TMJs that had been taken in 2005 and 2006 from 72 subjects born between 1930 and 1932 and between 1950 and 1952, respectively, the condylar position at closed jaw was calculated as percentage displacement of the condyle from absolute centricity. By using the criteria introduced by Orsini et al. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 86:489-97, 1998), a textbook-like disc position at closed jaw was distinguished from an anterior location. TMJ morphology of the temporal joint surfaces was assessed at open jaw by measuring the depth of the glenoid fossa, using the method proposed by Muto et al. (J Oral Maxillofac Surg 52:1269-72, 1994). Frequency distributions were recorded for the condylar and disc positions at closed jaw. Student's t-test with independent samples was used as test of significance to detect differences of condylar positions between the age cohorts (1930 vs. 1950) and the sexes. The significance levels were set at 5%. First, the results from the measurement of the age cohorts were compared without differentiation of sexes, i.e., age cohort 1930-1932 versus age cohort 1950-1952. Subsequently, the age cohorts were compared by sex, i.e., men in cohort 1930-1932 versus men in cohort 1950-1952, and women in cohort 1930-1932 women men in cohort 1950-1952. RESULTS: In both cohorts, condylar position was characterized by great variability. About 50% of the condyles were located centrically, while the other half was either in an anterior or in a posterior position. In both female cohorts, a posterior position predominated, whereas a centric position prevailed among men. Around 75% of the discs were positioned textbook-like, while the remaining forth was located anteriorly. Age had no statistically significant influence on condylar or on disc position. Conversely, comparison between the age groups revealed a statistically significant decrease of the depth of the glenoid fossa in both older cohorts. This age-dependent changes may be interpreted as flattening of the temporal joint surfaces. CONCLUSIONS: We call for a re-interpretation of imaging findings because they may insinuate pathology which usually is not present. Instead, anterior or posterior positions of the mandibular condyle as well as an anterior location of the articular disc should be construed as a variation of normalcy. Likewise, flattening of articular surfaces of the TMJs may be considered as normal adaptive responses to increased loading, rather than pathological degenerative changes. TRIAL REGISTRATION: Not applicable.

Digital Michigan splint - from intraoral scanning to plasterless manufacturing.

AIM: To investigate whether the fully digital, plasterless fabrication of clinically usable Michigan splints can be accomplished in a time- and cost-efficient manner. MATERIALS AND METHODS: Digital scans of the maxillary and mandibular arches of 10 subjects were acquired with an intraoral scanner (3Shape, Copenhagen) and used to generate virtual models of the dental arches. Jaw relation records were made using jigs placed on the subjects' anterior teeth, and silicone registration material was referenced to the jaw models. The data sets were then sent via the company's online portal to the dental laboratory, where computer-aided design (CAD) of the Michigan-type maxillary splints was performed. After receiving the designs, the splints were milled in-office using computer-aided manufacturing (CAM) software, and finished manually. During try-in, the splints where checked for fit, retention quality, and occlusal contacts of the mandibular teeth on the splint surfaces in static and dynamic occlusion. RESULTS: Fit and retention were clinically acceptable in 10 splints and 9 splints, respectively. The number of initial occlusal contacts on the splint surfaces ranged from 4 to 16. CONCLUSIONS: The question addressed in this study can be answered in the affirmative. Some of the main advantages of digital manufacturing of Michigan splints over traditional, conventional, impression-based manufacturing are the time-efficient manufacturing process, the high material quality, and the possibility of manufacturing duplicate splints.

Motion analysis of the mandible: guidelines for standardized analysis of computer-assisted recording of condylar movements.

Mandibular movement recording has long been established as the method for the physiological design of indirect dental restorations. Condylar movement recording is the basis for individual, patient-specific programming of partially or fully adjustable articulators. The settings derived from these recordings can generally be used in both traditional mechanical and electronic virtual articulators. For many years, condylar movement recordings have also provided useful information about morphological conditions in the temporomandibular joints (TMJs) of patients with masticatory system dysfunction based on the recorded movement patterns. The latest clinical application for recorded jaw-motion analysis data consists of functional monitoring of the patient as a diagnostic and surveillance tool accompanying treatment. Published parameters for the analysis of such recordings already exist, but a standardized and practicable protocol for the documentation and analysis of such jaw-movement recordings is still lacking. The aim of this article by a multicenter consortium of authors is to provide an appropriate protocol with the documentation criteria needed to meet the requirements for standardized analysis of computer-assisted recording of condylar movements in the future.

Condylar motion analysis: a controlled, blinded clinical study on the interindividual reproducibility of standardized evaluation of computer-recorded condylar movements.

The present study investigated to what extent a systematic evaluation of electronic condylar motion recordings leads to reproducible results in different examiners. The study was based on the anonymized condylar motion recordings of 20 patients (Cadiax compact II system). These were recruited consecutively from the examinations in a center specializing in diagnosing and managing temporomandibular disorders (TMD). Four trained practitioners independently evaluated the identical movement recordings of all patients after calibration. The evaluation was based on the previously published evaluation system. The results were recorded digitally in a database. The findings were then compared, and the matching values were determined (Fleiss' Kappa). The evaluation, according to Fleiss' Kappa, showed that the consistency of the assessment of the findings among the examiners is excellent (mean value 0.88, p < 0.00001). The study shows that calibrated dentists achieved reproducible results using this evaluation system and computer-assisted reporting. Good reproducibility confirms the reliability of systematic evaluation of clinical motion analysis. The ambiguities uncovered and eliminated in the study should avoid misunderstandings in the future. Both factors establish the prerequisites for applying condylar motion analysis in clinical practice.

Muscle and joint forces under variable equilibrium states of the mandible.

It is well established that subjects without molars have reduced ability to comminute foods. However, epidemiological studies have indicated that the masticatory system is able to functionally adapt to the absence of posterior teeth. This supports the shortened dental arch concept which, as a prosthetic option, recommends no replacement of missing molars. Biomechanical modeling, however, indicates that using more anterior teeth will result in a larger temporomandibular joint load per unit of bite force. In contrast, changing bite from incisor to molar position increases the maximum possible bite force and reduces joint loads. There have been few attempts, however, to determine realistic joint loads and corresponding muscular effort during generation of occlusal forces similar to those used during chewing with intact or shortened dental arches. Therefore, joint and cumulative muscle loads generated by vertical bite forces of submaximum magnitude moving from canine to molar region, were calculated. Calculations were based on intraoral measurement of the feedback-controlled resultant bite force, simultaneous electromyograms, individual geometrical data of the skull, lines of action, and physiological cross-sectional areas of all jaw muscles. Compared to premolar and canine biting, bilateral and unilateral molar bites reduced cumulative muscle and joint loads in a range from 14% to 33% and 25% to 53%, respectively. During unilateral molar bites, the ipsilateral joints and contralateral muscles were about 20% less loaded than the opposing ones. In conclusion, unilateral or bilateral molar biting at chewing-like force ranges caused the least muscle and joint loading.

Limited evidence that acupuncture is effective for treating temporomandibular disorders.

DATA SOURCES: Medline, PubMed, The Cochrane Library 2010, CINAHL, Embase, seven Korean Medical Databases and a Chinese Medical Database (China Academic Journal, www.cnki.co.kr). STUDY SELECTION: Parallel or cross-over RCTs that assessed the efficacy of acupuncture regardless of blinding, language and type of reporting published in English, Chinese and Korean were included. Dissertations and abstracts were included provided they contained sufficient detail. Complex interventions in which acupuncture was not a sole treatment and studies with no reported clinical data were excluded. DATA EXTRACTION AND SYNTHESIS: All RCTs were obtained and read in full by two independent reviewers and data extracted according to pre-defined criteria. Quality was assessed using the Cochrane risk of bias criteria. Meta-analysis was conducted using random effect models if excessive statistical heterogeneity did not exist. Additional subgroup analysis or sensitivity analysis additionally was conducted to explore heterogeneity. Publication bias was assessed by funnel plot using the Cochrane software. RESULTS: Seven RCTs (including 141 patients) met our inclusion criteria. Six studies comparatively tested needle acupuncture against penetrating sham acupuncture, non-penetrating sham acupuncture or sham laser acupuncture, whilst the remaining study tested laser acupuncture against sham laser acupuncture. Five studies were considered to be at low risk of bias. Outcomes were reported for pain intensity, facial pain, muscle tenderness and mouth opening. CONCLUSIONS: This systematic review produced limited evidence that acupuncture is more effective than sham acupuncture in alleviating pain and masseter muscle tenderness in TMD. Further rigorous studies are, however, required to establish beyond doubt whether acupuncture has therapeutic value for this indication.

[Dentistry in Wikipedia: A quantitative and qualitative analysis]. / Die Zahnmedizin in Wikipedia: eine quantitative und qualitative Analyse.

The aim of this study was to assess the scientific quality of the 265 dental articles that were present in January 2008 in the German-language version of Wikipedia. For this purpose, the Wikipedia entries were examined for their correctness by comparing them with the current dental literature. Every article was classified as having "textbook quality", "partial textbook quality" or "missing textbook quality". Of the 261 usable articles, 28% were qualitatively comparable to a textbook, while 56% had partial textbook quality. About 16% of the articles fell into the third group. Almost half of the Wikipedia entries fulfilled the qualitative standards, whereas the remaining articles were characterized by omissions. Hence, individuals interested in dental topics should not exclusively rely on Wikipedia. For a cursory overview, however, a search in Wikipedia appears to be in order.

Medication effects on the rate of orthodontic tooth movement: a systematic literature review.

INTRODUCTION: Recently, several reviews have been published on the effects of medications on bone physiology and the clinical side effects in orthodontics. However, the effects of medications on the rate of orthodontic tooth movement have not been evaluated. METHODS: A systematic literature review on the effects of medications and dietary supplements on the rate of experimental tooth movement was performed by using PubMed (1953-Oct 2007), Web of Science, and Biosis, complemented by a hand search. RESULTS: Forty-nine articles were included in the review, but their interpretation was hindered by the variability in experimental design, magnitude of force applied during tooth movement, and medication regimens. Therapeutic administration of eicosanoids resulted in increased tooth movement, whereas their blocking led to a decrease. Nonsteroidal anti-inflammatory drugs (NSAIDs) decreased tooth movement, but non-NSAID analgesics, such as paracetamol (acetaminophen), had no effect. Corticosteroid hormones, parathyroid hormone, and thyroxin have all been shown to increase tooth movement. Estrogens probably reduce tooth movement, although no direct evidence is available. Vitamin D3 stimulates tooth movement, and dietary calcium seemed to reduce it. Bisphosphonates had a strong inhibitory effect. CONCLUSIONS: Medications might have an important influence on the rate of tooth movement, and information on their consumption is essential to adequately discuss treatment planning with patients.

Surface microbial contamination in a dental department. A 10-year retrospective analysis

Health care-associated infections may not only occur in a hospital setting, but also in dental clinics. Insufficient environmental decontamination could be one of the risk factors. In this retrospective study, we documented and analyzed the results of surface microbial contamination in a dental university-based department over an observation period of ten years. It was the aim of this investigation to identify general tendencies and potentially problematic sites on a long-term basis allowing suggestions for further improvement. Surface microbial contamination in the Department of Reconstructive Dentistry at the University Center for Dental Medicine in Basel, Switzerland, was evaluated on a regular basis using contact plates. Data gained between January 2007 and December 2016 was collected and summarized for statistical analysis. Although the overall surface microbial contamination was relatively low during the observation period, significant differences depending on localization and test sites were detected. Certain sites, such as the handle of the dentist's chair and computer surfaces, remained problematic. Continuous monitoring of surface microbial contamination can help to improve the hygiene level in a dental set-up. Further improvement might be achieved by avoiding hand-touch handles whenever possible and by relying on flat and easy-to-clean surfaces within the reach of the bacterial aerosol. However, during interventions that may pose a higher risk for the patient, additional measures should be taken by working under almost sterile conditions and by avoiding direct hand contact with problematic sites.

Motor behavior of the jaw muscles during different clenching levels.

The goals of this study were to investigate whether (i) muscle activities are affected by different feedback strategies, (ii) the balancing behavior of the neuromuscular system is influenced by different force levels, and (iii) axial loading of the posterior teeth is a realistic biomechanical conception. In 10 healthy subjects, all jaw muscles were recorded bilaterally. Intra-oral force transfer and force measurement were achieved by using a measuring device simulating natural maximum intercuspation. Under visual feedback-control, the subjects generated pure vertical and directionally unrestricted force vectors with identical force magnitude at different force levels. The force transmission characteristics under experimental occlusion were investigated by calculating the reduction point (RP) of the resultant bite force. Directionally unrestricted clenching revealed a higher activation of the musculature than pure vertical clenching and was also characterized by a distinct anterior force component. Under both test conditions, the RP moved towards a posterior position with increasing clenching forces. The results indicate an essential recruitment difference of the jaw muscles between the two clenching conditions. Pure axial loading of teeth seems to be impeded by the anterior force component during bilateral clenching. The posterior movement of the RP might prevent overloading of the temporomandibular joints and anterior teeth.

The NTI-tss device for the therapy of bruxism, temporomandibular disorders, and headache - where do we stand? A qualitative systematic review of the literature.

BACKGROUND: The NTI-tss device is an anterior bite stop, which, according to the manufacturer, is indicated for the prevention and treatment of bruxism, temporomandibular disorders (TMDs), tension-type headaches, and migraine. The aim of this systematic review was to appraise the currently available evidence regarding the efficacy and safety of the NTI-tss splint. METHODS: We performed a systematic search in nine electronic databases and in NTI-tss-associated websites (last update: December 31, 2007). The reference lists of all relevant articles were perused. Five levels of scientific quality were distinguished. Reporting quality of articles about randomized controlled trials (RCTs) was evaluated using the Jadad score. To identify adverse events, we searched in the identified publications and in the MAUDE database. RESULTS: Nine of 68 relevant publications reported about the results of five different RCTs. Two RCTs concentrated on electromyographic (EMG) investigations in patients with TMDs and concomitant bruxism (Baad-Hansen et al 2007, Jadad score: 4) or with bruxism alone (Kavakli 2006, Jadad score: 2); in both studies, compared to an occlusal stabilization splint the NTI-tss device showed significant reduction of EMG activity. Two RCTs focused exclusively on TMD patients; in one trial (Magnusson et al 2004, Jadad score: 3), a stabilization appliance led to greater improvement than an NTI-tss device, while in the other study (Jokstad et al 2005, Jadad score: 5) no difference was found. In one RCT (Shankland 2002, Jadad score: 1), patients with tension-type headache or migraine responded more favorably to the NTI-tss splint than to a bleaching tray. NTI-tss-induced complications related predominantly to single teeth or to the occlusion. CONCLUSION: Evidence from RCTs suggests that the NTI-tss device may be successfully used for the management of bruxism and TMDs. However, to avoid potential unwanted effects, it should be chosen only if certain a patient will be compliant with follow-up appointments. The NTI-tss bite splint may be justified when a reduction of jaw closer muscle activity (e.g., jaw clenching or tooth grinding) is desired, or as an emergency device in patients with acute temporomandibular pain and, possibly, restricted jaw opening.

Restoring the fractured root-canal-treated maxillary lateral incisor: in search of an evidence-based approach.

OBJECTIVE: To demonstrate the existing difficulties and variability in the application of evidence-based dentistry by comparing the recommendations made by 4 dental experts for the treatment of a fractured tooth. METHOD AND MATERIALS: A case presentation was given to 4 specialists, who were asked to independently develop and explain their personal favorite treatment strategy, based on the best available external evidence and their clinical expertise. The entire case was then reviewed by an expert in evidence-based medicine and discussed with the first author. RESULTS: Each of the 4 experts relied on different articles in justifying their clinical decisions. The minimal overlap in the literature they cited largely explains the different treatment suggestions: While the endodontist preferred a metal post-and-core and a porcelain-fused-to-metal (PFM) crown, both the operative dentist and the prosthodontist opted for a glass-fiber post/fiber-reinforced resin composite post. The perio-prosthodontist recommended a PFM crown with either a direct or indirect post and core. The citation analysis revealed that little high-quality information is available about what would be the best therapy for horizontal fractures of root-canal-treated anterior teeth. CONCLUSIONS: This article illustrates that, although it is now common practice in dentistry to base clinical decision making on external evidence from the literature, search strategies and the resulting clinical recommendations still vary greatly.

Heterogeneous activation of the medial pterygoid muscle during simulated clenching.

The aim of this study was to investigate whether the medial pterygoid muscle shows differential activation under experimental conditions simulating force generation during jaw clenching. To answer this question, the electromyographic activity of the right medial pterygoid was recorded with two intramuscular electrodes placed in an anterior and posterior muscle region, respectively. Intraoral force transfer and force measurement were achieved by a central bearing pin device equipped with strain gauges. The activity distribution in the muscle was recorded in a central mandibular position during generation of eight different force vectors at a constant amount of force (F=150 N). The investigated muscle regions showed different amounts of EMG activity. The relative intensity of the activation in the two regions changed depending on the task. In other words, the muscle regions demonstrated heterogeneous changes of the EMG pattern for various motor tasks. The results indicate a heterogeneous activation of the medial pterygoid muscle under test conditions simulating force generation during clenching. This muscle behaviour might offer an explanatory model for the therapeutic effects of oral splints.

[Without risks and side effects? Product advertisements in dental journals]. / Ohne Risiko und Nebenwirkung? Produktwerbung in zahnmedizinischen Zeitschriften.

We examined number, size, design, and scientific approach of advertisements published in three dental journals between 1970 and 2004. For this purpose, the Schweizer Monatsschrift für Zahnmedizin (SMfZ), Zahnärztliche Mitteilungen (ZM; Ger many), and The Journal of the American Dental Association (JADA) were chosen. The January and July issues of each of the 35 volumes were analyzed. Of 28,711 pages, 7265.5 were identified as advertisements (JADA: 29.9%, SMfZ: 24.8%, ZM: 13.7%). While whole-page ads dominated in JADA (87.2%) and SMfZ (68.9%), ad-sizes were more balanced in ZM. During the observation period, the use of photographs increased, while that of drawings decreased. Images of products dominated as compared to pictures of the orofacial region. Citations from study results (SMfZ 3.3%: ZM 2.5%; JADA 5.5%) and diagrams/tables (SMfZ: 3.2%; ZM: 1.0%; JADA: 4.5%) were rarely used, and an appreciable number of cited references could not be identified (SMfZ: 16%, ZM: 18%). More than 80% of the identifiable cited references corroborated the claim made in the advertisement. However, a critical attitude towards ads in dental journals appears justified.